Hey @JoeyJWK,

Thanks for getting in touch! 
 

While we're not able to discuss specific transaction information via our seller community, what you're describing is something Amex are doing on their end.

Speaking in general terms, this commonly occurs with international credit card transactions. It wouldn't be that Amex specifically consider Square or yourself unsafe - Amex are one of our largest finance partners. If they are indeed international transactions, it's more likely the transactions are being flagged because they have been processed in a location far removed from where the customer's regular card activity is based. 

If it's a corporate card, it's also possible that transactions outside the country, or at certain business types, are more heavily restricted and require additional approval. Often the end users of corporate cards are unaware that their own company has intentionally placed restrictions on what sort of businesses the card can be used at. 

Unfortunately, as annoying as it is, this is something that falls out of your control and Square's control. I recommend that your customer talks to Amex and checks to see if there are any restrictions on the card and what these are, and whether it's possible to take a more relaxed approach to transactions with your business.

Let me know if you have any questions!